Mercedes W204 W212 OM651 Diesel High Pressure Injection Fuel Pump A6510701701

Mercedes W204 W212 OM651 Diesel High Pressure Injection Fuel Pump is a precision component of the diesel engine fuel supply system, designed for the Diesel units of this series. It is responsible for generating the required fuel pressure in the fuel rail, which translates into stable engine operation, correct injection doses, and predictable performance. Using a component from this group allows for a technically efficient repair without the need to invest in a new part.

Specifications and technical data

• SKU: A6510701701
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A6510701701
• Substitutable numbers: A6510701701, A 651 070 17 01
• Fuel type: Diesel
• Category: Fuel Pumps & Sending Units

Purpose and function in the fuel supply system

The described high-pressure injection pump operates in the Common Rail system of a diesel engine, ensuring sufficiently high fuel pressure for the injectors. A properly selected injection pump for the OM651 unit allows for maintaining:

• stable pressure in the fuel rail across the full load range,
• correct injection dose formation throughout the entire RPM range,
• smooth engine operation at idle and under load,
• a controlled level of exhaust emissions in accordance with the unit's design specifications.

Thanks to this, the Diesel engine injection pump is a key element in resolving issues with starting, power loss, or uneven engine performance.

Benefits of using an original Mercedes pump

Choosing an injection pump from the Mercedes group primarily ensures structural compatibility with the fuel system of a specific engine series. The original component provides:

• compliance with the factory operating characteristics of the OM651 unit,
• proper cooperation with pressure sensors and the engine control unit (ECU),
• appropriate performance characteristics for the Diesel system,
• the ability to install it in place of the old pump without interfering with the fuel system construction.

A used element from this group, when correctly selected based on the part number and engine configuration, represents a reasonable service solution in the event of a fuel system failure.

Condition, selection, and installation aspects

The injection pump is offered as a part from the Fuel pumps and level sensors category in a used condition, which allows for an economical repair while maintaining the factory design. Before installation, it is recommended to:

• verify compatibility using the OEM part number and interchangeable numbers,
• check the engine configuration and fuel type (Diesel),
• inspect the cleanliness of the fuel system (filter, lines, tank),
• properly bleed the system after installation.

Professional installation by a workshop familiar with the specifics of Common Rail systems in Mercedes vehicles minimizes the risk of leaks, bleeding problems, and engine control unit errors.

Technical support and additional information

When selecting used fuel system components, correct identification by OEM number and reference numbers, as well as matching to the specific engine version, is particularly important. In case of doubt, it is worth consulting a mechanic or the store's technical department, providing the vehicle data and engine unit designation.

If you are planning a comprehensive repair or upgrade of the fuel system area in your Mercedes and need other elements from the same group, such as supply pumps, in-tank pump modules, or fuel level sensors, check the available parts in the Mercedes fuel pumps and level sensors category.

When choosing used fuel system components and control electronics, it is worth learning about good selection and installation practices – you can find practical tips in the article The second life of electronics – when is it worth choosing used engine controllers, comfort modules, and parking sensors?, which helps you approach the purchase of second-hand parts consciously.